1. Technical Field
The present invention relates to a physical quantity sensor, a sensor device, an electronic apparatus, and a moving object.
2. Related Art
As a physical quantity sensor that detects a physical quantity such as acceleration or an angular velocity, a so-called seesaw type sensor is known (for example, refer to JP-A-2013-040856). For example, the physical quantity sensor disclosed in JP-A-2013-040856 includes a base substrate, a sensor portion which is oscillatably supported by the base substrate and on which a movable electrode portion is provided via the center of oscillation axis on each of one side and the other side, and a fixed electrode portion that is provided on the base substrate so as to face each movable electrode portion. In such a physical quantity sensor, it is possible to detect a physical quantity such as acceleration or an angular velocity based on an electrostatic capacitance between the movable electrode portion and the fixed electrode portion.
In addition, in the physical quantity sensor disclosed in JP-A-2013-040856, a sensor unit is disposed on the upper portion of a first concave portion provided in the base substrate. In addition, on a surface in a sensor unit side of the base substrate, a second concave portion of which a depth is deeper than the first concave portion is provided at a superimposed position in a plan view seen from a tip of the sensor unit. In this way, it is possible to reduce gas damping between the sensor unit and the base substrate.
In the above-described physical quantity sensor disclosed in JP-A-2013-040856, a fringe capacitance generated between the movable electrode and the fixed electrode portion in one side and a fringe capacitance generated between the movable electrode and the fixed electrode portion in the other side are different from each other. In the related art, in a state in which a physical quantity is not applied to the sensor unit, an amount of electrostatic capacitance offset which is a difference between the electrostatic capacitance between the movable electrode and the fixed electrode portion in one side and the electrostatic capacitance between the movable electrode and the fixed electrode portion in the other side increases due to the difference between the two fringe capacitances. As a result, there has been a problem in that the detection accuracy deteriorates.